First - Notice how he "rips" the plastic wrap from the back, moving the box almost completely off camera when he does, so you don't see it's just kitchen plastic wrap.

Second - notice how when he opens the box, THERE IS A PLASTIC STICKER SEAL ON THE FLAP, AND IT'S ALREADY BEEN CUT! You can see the ragged edge at roughly the 33-35 second mark, he just opens the box with the flat of his thumb without breaking the seal, cuz it's already cut open...

Third - really, everybody in chorus screams the exact same thing (which by the way is profanity and not appropriate for Beckett..)

''I've never been in style, so I can never go out of style." - Lillian Gish ( 1
893 - 1993)